Improvement in take-up and tension springs for wax-thread sewing-machines



;;J. B. SULGROVE. Take-Up and Tension-Spring for Wax-ThreadSewing-Machines.

No. 211,355. Patented Jan. 14,1879.

.State of Indiana, useful Combined Self-Adjustable Tension and U ITEDSTATES "PATENT FFIGE.

JOSEPH B. SULGROVE, OF INDIANAPOLIS, INDIANA, ASSIGNOR TO MARY LlSULGROVE, OF SAME PLACE.

IMPROVEMENT IN T AKBUP AND TENSION SPRINGS FOR WAX-THREADSEWING-MACHINES.

Specification forming part of Letters Patent No. 211,355, dated January14, 1879 application filed September 9, 1878. I j

To all whom it may concern:

.Be it known that I, J osnrH B. SULGROVE, of Indianapolis, in the countyof Marion and have invented a new and Take-Up Spring for Waxed-ThreadSewing- .Machines, of which the following is a description, referencebeing had to the accompanying drawings.

My invention relates to a combined take-up and tension spring forsewing-machines using 'a single waxed thread.

Previous to my invention waxed-thread sewing-machines using a singlethread have required at least five adjustments of various 'parts inorder to adapt the machine to all grades of sewing, such as shoe andharness 'work, especially the latter, where various thicknesses ofmaterial have to be'united together. The adjustments required are asfollows,- to wit: first, the take-up mechanism; second,

the adjustment of the tension of the thread; third, the adjustment ofthe length of stitch;

fourth, the adjustment of the needle and castoft; and, fifth, theadjustment of the needle with respect to the awl and the stroke of thepressure-foot vertically. The adjustment of the stroke of the needle andcast-off, and also of the needle relative'to the'position of the awl,are, in. waxed-thread machines, in excess of any adjustment heretoforenecessary in the ordinary dry-thread machines, and these extraadjustments have been of such vital importanee in a waxed-thread.machine that they have necessitated a change of adjustment of thoseparts whenever the thickness of material that is to be sewed varies.Thus, if the material to be sewed is one-fourth of an inch thick, theneedle-bar has usually been adjusted with a stroke of fifteen-sixteenthsof an inch, and the hook or barb of the needle adjusted to rise one-halfinchabovethe throat-plate, and also to descend below the surface of thethroatplate seven-sixteenths of an inch, the stroke of the needlerequiring a new adjustment in length for each additional thickness ofmaterial sewed, and a corresponding rednction in length of stroke formaterial of less thickness otherwise-t the thread would form loops toolarge or too small forthe required stitch, while the surplus threaddrawn from thetensionwheel is permitted to seesaw hook of the needleuntil it is damaged by chafing and frequently broken. When the stitch insuch machines is increased in length, then the needle-bar has to beagain adjusted witha corresponding increase in its stroke, which must beadded below the throat-plate in order to draw an additional amount ofthread necessary to form the loop required for the lengthened stitch.

It is obvious that in making the necessary adjustments of parts as abovedescribed in the ordinary waxed-thread machines, con siderable time islost, and that with the most explicit instructions it will require askilled artisan to keep the machine in good workin the eye or "mg order;and it is impossible for manufac 'turers of such machines to send amachine with its needle-bar, awl, andtake-up adjusted ready for allkinds of work, or, in fact, for any kind of work, unless the workrequired is specially mentioned in the order for the machine.

The object of my invention is to do away with the various verticaladjustments of the needle-bancast-ofi, and awl, as above described in awaxedthread sewing-machine, and to provide such machines with anautomatic,

self-regulating, combined take-up and tension spring, whereby theneedle-bar, cast-ofi', and awl, when once adjusted to the longest strokethat the thickest part of the work requires, needs no further adjustmentvertically. for thick or thin work. The only adjustment required of theneedle is its movement horizontally for lengthening or shortening thestitch when the machine has a needle-feed, (while in those machines thatare provided with an awlfeed no such adjustment of the needle isrequired,) and the stitches, whether coarse or fine, whether throughthick or thin material, whether of light, medium, or heavy thread, arealways drawn tight, with no loose loops or slack thread left in thework, and no seesawing of thread in the hook of the needle, because allsurplus thread that slides one way in the hook of the needle is formedinto a loop and left in the material, thus rendering the now difficultto be adjusted and operated waxed-thread machine as simple in itsoperation as any of the ordinary dry-thread machines.-

My invention consists of the new construction and arrangement of parts,and in the new combination of new and-old elements that are deemedessential for operating my newly-combined selfadjustable take up andtension spring, as willbe hereinafter fully described and set forth.

In the accompanying drawing, in which like letters of reference in thedifferent figures indicate like parts, Figure 1 represents a sideelevation of the head and post of a waxedthread sewing machine, showinga side View of my combined take up and tension spring adjusted ready foruse. Fig. 2 is an end view of the same, and Fig. 3 is a view of thecombined take-up and tension spring detached from the head of themachine.

The combined take-up and tension spring is represented as attached tothe head of a New England VVax-Thread Sewing-Machine, but it is equallyadapted to the National Wax- Thread Sewing-Machine, or any othersinglethread machine designed to be used in the manufacture of all kindsof leather articles.

A represents the arm of the machine, and B the head. At the lower rearpart of one side of the head is attached an arm, P, by means of a screw,P. The tension wheel 0 is mounted on the screw stud 0 that is secured tothe arm P, and is provided with a coil-spring, O and adjusting-nut O inthe usual manner. 0 is the awl-bar; D, the threadcarrier bar M, thethread-carrier I, the presser-foot bar; X, the presser-foot; N, the awl;U, the post; U, the throat-plate; W, the cast-01f V, the needle, and Vthe needle-bar, all of which are of the ordinary form now in use.

The take-up and tension spring H H is of peculiar con struction, to wit:The outer spring, H, is bent into a curve, with a curved hook, H at oneend, for the purpose of forming a means of fastening the device to thestud P, as shown in Figs. 1 and 3. .The other end of the curved spring His provided'with a threadhook, S; and two other hooks, S S are attachedto the spring, a short distance above, as shown. At or near the top ofthe spring H, nearest to the thread-hooked end, is a stop, G, with arubber or leather cap, that acts against the adjusting-screwE. The outercurved spring, H, if used alone, would have to be made so stiff thatsome of its various actions would be impaired, and it would not have thequick, yielding, and flexible qualities required to adapt it to thevarious uses and purposes which it'is designed to accomplish. Hence theouter curved spring, H, is made of light, active spring material, and isprovided with another curved active spring, H, that is attached thereto,forming a compound crescent-shaped sprin gthat is extremely quick andsensitive in its action, and yet yielding enough to accomplish thevarious ends required. One end of the curved spring H 'is' secured tothe outer spring, 1-1, at H and the other end of the inner spring issecured-to the outer curved spring at or near the stop G, thus forming acurved flexible brace to the outer spring, extending from the fasteningH to the stop G, while the part H of the outer spring, with the threadhooks S S S extending beyond the inner spring, is

allowed an independent springmotion toward and from the hook end H aswill be hereinafter described. 1

The light coil take-up spring K has one end securely fastened to thehook end H of the compound tension-sprin g H H and the other endprojects toward-the lower thread-hook S, and is provided with a loop, L,as shown, the operation of which will be hereinafter fully described. v

Immediately over the stop G of the spring H H is a stud, R, secured tothe head B, as shown in Fig. 2. The outer end of said stud is providedwith a vertical hole, having a screw-thread cut therein for theadjustingscrew E to operate in, and said screw is held at any requiredadjustment by the jam-nut F, as shown.

The operation of the machine with the combined take-up and tensionsprings, together with the new results produced, are as follows, to wit:First, the needle and cast-off, together with the awl and presser-foot,being once adj usted for the thickest part of work to be sewed, themachine is then adjusted for any thickness of material, and requires nofurther adjustment except for length of stitch, which is accomplished bygiving the needle more or less horizontal movement, (but no lengtheningor shortening of the stroke of the needle-bar is required.) The threadis drawn from its ball and passed through the waxcup and around thetension-wheel O, in the usual manner, after which it is carried over oneof the thread-hooks, S, of the take-up and tension spring H H then downthrough the wire loop L of the small coil take-up spring K; then downthrough the threadguide, which partially rotates around the needle. Thedriving-wheel of the machine (not shown) is then revolved until theneedle is at the lowerendof the stroke. Then the materialthat is to besewed is placed on the throat-plate U of the post, and thepresser-footlowered upon it. The driving-wheel is then revolved slowly until thefirst stitch is secured, and then the machine is ready for operation.

As the awl-bar descends, the awl N punches a hole, and the needle,following the awl up, enters the hole and passes up until the hook orbarb is some distance-say seven-eighths of an inch-above thethroat-plate. At the same time the thread-carrier M is partiallyrevolved, carryin g the thread around the needle below the hook or eye.The take-up spring L holds the thread taut, and throws it into the eye'or hook as the needle descends and moves horizontally to effect thefeed. The eye or hook of the nee-v dle, as it enters the material in itsdownward motion, draws the thread from above on the spring H H, whichsprings slightly and tightens the former loop around the cast-01f below.The double thread or loop carried down by the hook passes through thehole, and at the same time the double spring H H is drawn slightly downfrom the adjiisting screw E, the spring H H having a tension given to itby the adjusting-screw E sufficient to draw the thread and to allow thespring H H to yield and letthe double thread pass through the leatherwithout breaking it. As the needle with the loop continues going downbelow the material the thread slides slightly one way in the eye of theneedle (not seesawing) as it draws the thread from above. The spring H Hat the same time is recovering its position, so that when the needlereaches its lowest point the stop G has moved up against the adj usting-screw E, with the thread just stretched taut, with but slight tensionon it,'and that tension is caused by the straightening out of the part Hof the spring H and the slight tension given by the small spring K L. Asthe needle and cast'oft' come up, the loop just formed is loose enoughfor the cast-oft'to come between the thread and needle, while theprevious loop slips off of the cast-oft around the loop just formed;otherwise the loop would get into the eye again and the cast-off couldnot get between the thread and needle, and, 0011- sequently, when thenext stitch is made, the needle would cut the thread.

As the needle reaches its lowest point it fin ishes the drawing of thecast-oft'loop up tightly under the m aterial sewed, and part ofthethread in tightening the loop is drawn up through the next to thelast hole made by the awl over the work, and down through the last holeby the downward movement of the needle below the the spring, whichcauses an increase in tension proportional to the increase inpowerrequired to make the loop and stitch tight and the spring H H yield.Medium-size thread is used in the hook S and light thread in hook S. Thetensionpower of the spring H H and length of thread drawn for eachstitch are regulated .by the amount of adjustment of the screw E-thatis,should the screw E just touch the stop G, with no pressure thereon, thedownward movement of the needle would draw the would not draw the stitchtight enough in the work, as it would only act as a slight take-up butwhen the screw E is rundown so that the spring H H is under considerablepressure, then the downward stroke of the needle draws the previousstitch tightly, and the spring H H yields and draws the stop Gr slightlyaway from the screw E until the double thread is through the material.Then the spring H H begins to move up against the screw E;-but the partH is still under sufficient strain to tighten the loop around thecast-off until the needle starts up again, when the operation is againrepeated.

It will be seen from the foregoing that with my new combined take-up andtension-spring all manner of work, thick or thin, can be performed onany single waxedthread sewing machine with but one adjustment of theneedle, cast-oft, and awl, and that when the tension is once adjusted toany length of stitch, the stitch may be lengthened or shortened withoutreadjustment of said tension, unless the tension should be so strong as,in making 1. In a waxed-thread sewing-machine, the

take-up ten sion-sprin g H, having thread-hooks S 8 S stop Gr, andtake-up spring K, com: bined with the head 13 and adj ustin g-screw E,whereby the tension and takenp action of the spring H is increased ordiminished, substantially as shown and described.

2. In a waxed-thread sewingmachine, the take-up tension-spring H Hcombined with the head B, tension-wheel 0, adj Listing-screw E, andtake-up spring K L, substantially as shown and described.

3. The compound takenp tension-spring composed of the outer spring, H,and inner spring, H}, the thread-hooks S S S stop G, and the hook H forfastening, substantially as shown and described.

4. The take-up tension-spring H H, having the take-up spring K, providedwith a loop or hook, L, rigidly secured thereto, substantially as shownand described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

JOSEPH 13. SULGROVE.

Witnesses:

E. O. FRINK, M. H. Orr.

